Nuclei

Nuclei
Nucleus Nu"cle*us, n.; pl. E. {Nucleuses}, L. {Nuclei}. [L., a kernel, dim. fr. nux, nucis, nut. Cf. {Newel} post.] [1913 Webster] 1. A kernel; hence, a central mass or point about which matter is gathered, or to which accretion is made; the central or material portion; -- used both literally and figuratively. [1913 Webster]

It must contain within itself a nucleus of truth. --I. Taylor. [1913 Webster]

2. (Astron.) The body or the head of a comet. [1913 Webster]

3. (Bot.) (a) An incipient ovule of soft cellular tissue. (b) A whole seed, as contained within the seed coats. [1913 Webster]

4. (Biol.) A body, usually spheroidal, in a eukaryotic cell, distinguished from the surrounding protoplasm by a difference in refrangibility and in behavior towards chemical reagents, which contains the chromosomal genetic material, including the chromosomal DNA. It is more or less protoplasmic, and consists of a clear fluid (achromatin) through which extends a network of fibers (chromatin) in which may be suspended a second rounded body, the nucleolus (see {Nucleoplasm}). See {Cell division}, under {Division}. [1913 Webster +PJC]

Note: The nucleus is sometimes termed the endoplast or endoblast, and in the protozoa is supposed to be concerned in the female part of the reproductive process. See {Karyokinesis}. [1913 Webster]

5. (Zo["o]l.) (a) The tip, or earliest part, of a univalve or bivalve shell. (b) The central part around which additional growths are added, as of an operculum. (c) A visceral mass, containing the stomach and other organs, in Tunicata and some mollusks. [1913 Webster]


The Collaborative International Dictionary of English. 2000.

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  • NUCLEI — (лат. ядра), в нервной системе скопления клеточных элементов, объединенных между собой общностью функции. Ядра находятся повсюду в центральной нервной системе, особенно же их много в стволовой части (см. табл., ст. 631); они принадлежат к церебро …   Большая медицинская энциклопедия

  • nuclei — [no͞o′klē ī΄, nyo͞o′klē ī΄] n. pl. of NUCLEUS …   English World dictionary

  • nuclei — /nooh klee uy , nyooh /, n. pl. of nucleus. [ < L nuclei, nom. pl. of nucleus; see NUCLEUS] * * * …   Universalium

  • nuclei — Plural of nucleus. * * * nuclei pl of NUCLEUS * * * nu·clei (nooґkle i) [L.] genitive and plural of nucleus …   Medical dictionary

  • nuclei — pl. of NUCLEUS. * * * nuclei pl. of nucleus …   Useful english dictionary

  • nuclei nervi glossopharyngei — nuclei of glossopharyngeal nerve: the nuclei of origin and termination of the glossopharyngeal nerve, located in the medulla oblongata, comprising the inferior salivatory nucleus, the rostral part of the nucleus ambiguus, and the nuclei of… …   Medical dictionary

  • Nuclei colliculi superioris — are groups of large cells in the middle gray layer of the superior colliculus and more laterally near the midbrain tegmentum.[1] References ^ Riley HA (1943). An Atlas Of The Basal Ganglia, Brain Stem And Spinal Cord (Based On Myelin Stained… …   Wikipedia

  • nuclei areae H H1 H2 — nuclei campi perizonalis …   Medical dictionary

  • nuclei of caudal colliculus — nuclei colliculi inferioris …   Medical dictionary

  • nuclei of cochlear nerve — nuclei cochleares …   Medical dictionary

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